This invention relates generally to a method and apparatus for agitating tanked fluids and more particularly to a combined fluid mixing and tank wall wiping device positionable within a fluid holding tank.
The invention is particularly applicable to use with flexographic printing ink systems and, accordingly, will be frequently described herein with particular reference to such systems. It must be appreciated, however, that the invention has much broader applicability and may find utility in the stirring and mixing of virtually any tanked fluid wherein it is desirable to avoid the formation of froth within the fluid mass or the buildup of dried fluid residues on the walls of the tank.
Various fluid agitators and mixers are well known in the art. In general, however, such devices fall short of providing an optimal means for maintaining physical and/or thermal homogeneity of a fluid while, at the same time, preventing the buildup and desiccation of the fluid on the walls of the tank.
One particular application wherein the above-described problems are encountered is in contemporary flexographic printing ink systems. Such ink systems generally utilize at least one ink conditioning tank wherein a quantity of ink is held. The viscosity of the ink within the conditioning tank is periodically adjusted through the addition of water. Thus, in order to maintain the desired viscosity of the fluid contained within the tank, it is desirable to thoroughly mix the added water with the ink while avoiding the formation of excessive frothing or foam within the fluid mass. Also, as the ink level in the tank decreases from use of the ink, it is desirable to continually wipe adherent fluids from the walls of the tank so as to prevent such fluids from congealing or desiccating on the walls of the tank. Accordingly, a single device which is capable of carrying out both of these functions would provide a substantial advancement in the art.
In response to this present need in the art, the invention described and claimed herein embodies an improved method and apparatus for agitating tank fluids and preventing the buildup of adherent fluids on the inner walls of the tank.